Best Lily Pipes for Aquariums: Glass Inflow and Outflow

Table of Contents

• What Are Lily Pipes?
• Why Aquascapers Use Lily Pipes
• Types of Lily Pipes
• Sizing Guide: Matching Hose Diameter
• Brands Compared
• Glass vs Acrylic vs Stainless Steel
• Cleaning and Maintenance
• Handling and Fragility
• Frequently Asked Questions

What Are Lily Pipes?

Lily pipes are glass (or glass-like) inflow and outflow fittings designed for canister filters. They replace the chunky plastic spray bars and intake strainers that ship with most canister filters, sitting elegantly over the rim of your aquarium and connecting to your filter hoses.

The outflow pipe features a flared, lily-shaped opening that disperses water gently across the surface. The inflow pipe draws water into the filter through a slotted opening, often incorporating a surface-skimming slit. Together, they create effective circulation while virtually disappearing against the glass of your tank.

Originally popularised by ADA (Aqua Design Amano) in Japan, lily pipes have become a staple of the planted aquarium hobby worldwide. In Singapore, they are readily available from local aquascaping shops, Shopee, Lazada and AliExpress.

Why Aquascapers Use Lily Pipes

The appeal of lily pipes extends beyond mere aesthetics, though aesthetics are certainly the primary driver:

• Visual cleanliness. Clear glass is far less obtrusive than grey or green plastic fittings. In a carefully designed aquascape, equipment visibility matters.
• Surface skimming. Many inflow designs include a surface-skimming feature that removes the protein film common in Singapore’s warm climate (28-32 degrees Celsius). This improves gas exchange and light penetration.
• Controlled flow pattern. The flared outflow distributes water evenly, reducing dead spots while avoiding overly strong currents that stress delicate plants or shrimp.
• Easy removal for cleaning. Lily pipes lift off the tank rim without dismantling the entire filter setup, making maintenance quicker.

Types of Lily Pipes

Several outflow designs exist, each producing a different flow pattern:

For inflow pipes, the main distinction is between a standard submerged intake and a surface-skimming intake. The skimmer type has a small slit at the waterline that draws in surface film. In Singapore’s warm, humid conditions, a skimming inflow is highly recommended — biofilm accumulates rapidly when room temperatures sit above 28 degrees Celsius year-round.

Sizing Guide: Matching Hose Diameter

Lily pipes must match your canister filter‘s hose diameter exactly. The two most common sizes are:

• 12/16 mm (inner/outer diameter) — used by smaller canister filters such as the Eheim Classic 250 (2213), Oase BioMaster 250, and most filters rated for tanks up to 150 litres.
• 16/22 mm — used by larger filters such as the Eheim Classic 350/600 (2215/2217), Oase BioMaster 350/600, and filters rated for tanks above 150 litres.

Some filters use non-standard hose sizes (for example, Fluval uses 16/22 mm on some models but has proprietary fittings on others). Check your filter’s specifications before purchasing. Adaptors exist but add bulk and potential leak points.

For a comprehensive look at canister filters and which pairs well with lily pipes, see our guide to the best canister filters for aquariums.

Brands Compared

For most hobbyists in Singapore, a budget glass set from VIV or a similar brand offers excellent value. At SGD 20-35 for a pair, you can afford to replace them if an accident happens. The glass quality is surprisingly good for the price, though the edges may be slightly less polished than premium brands.

Glass vs Acrylic vs Stainless Steel

Each material has its trade-offs:

Glass remains the overwhelming favourite among aquascapers. If you have children, cats, or a habit of bumping into your tank, acrylic or stainless steel may save you from repeated heartbreak and expense.

Cleaning and Maintenance

Algae will coat the inside of your lily pipes within weeks, especially in Singapore’s warm climate. Regular cleaning keeps them looking pristine:

Routine cleaning (every 2-4 weeks)

1. Disconnect the pipes from the filter hoses and carefully lift them off the tank rim.
2. Use a flexible pipe cleaning brush (available for SGD 5-10 on Shopee) to scrub the interior. Feed the brush through gently — do not force it around tight bends.
3. Rinse thoroughly under the tap and reinstall.

Deep cleaning (every 2-3 months)

1. Soak the pipes in a dilute bleach solution (1 part household bleach to 20 parts water) for 30-60 minutes. This dissolves stubborn green algae and biofilm.
2. Rinse thoroughly under running water for several minutes.
3. Soak in dechlorinated water with a double dose of water conditioner for 15 minutes to neutralise any residual bleach.
4. Rinse once more and reinstall.

Never use abrasive scouring pads on glass lily pipes. They will scratch the surface, making the pipes more visible and creating texture for algae to grip.

Handling and Fragility

Glass lily pipes break. It is not a question of if but when. Here are precautions to minimise the risk:

• Always use both hands when lifting pipes off the tank rim. The curved sections are stress points.
• Wet the hose before pushing it onto the pipe’s inlet. Dry silicone tubing grips glass too tightly and can snap it during fitting.
• Store pipes safely during water changes. Lay them on a towel, not on a hard surface where they can roll off.
• Keep spares. At SGD 15-30 for a budget glass set, having a backup pair in the cupboard avoids downtime when a pipe breaks at the worst possible moment.
• Consider pipe holders. Some brands sell silicone suction cup holders that secure the pipe to the glass, reducing the chance of it being knocked off.

If you are setting up a new aquascape and want advice on choosing the right lily pipes for your tank and filter combination, our team at Gensou’s aquascaping consultation service is happy to help. Drop by our showroom at 5 Everton Park, Singapore.

Frequently Asked Questions

Can I use lily pipes with a hang-on-back filter?

No. Lily pipes are designed exclusively for canister filters with external hose connections. Hang-on-back filters have integrated inflow and outflow mechanisms that cannot be replaced with lily pipes.

Do lily pipes reduce flow rate compared to standard plastic fittings?

Slightly, yes. The flared outflow opening disperses flow over a wider area, which reduces the velocity at any single point. However, the total volume of water moved per hour remains the same — it is just distributed more gently. This is generally a benefit, not a drawback, for planted tanks.

My lily pipes keep getting algae even after cleaning. What can I do?

Persistent algae on lily pipes usually reflects an algae issue in the tank itself. Address the root cause — excessive light duration, nutrient imbalance, or insufficient CO2. Once the tank is balanced, algae growth on the pipes slows considerably. In Singapore’s warm conditions, reducing your lighting period to 7-8 hours often helps.

Are budget lily pipes from Shopee or AliExpress safe for aquarium use?

Generally, yes. Most are made from borosilicate or soda-lime glass, both of which are aquarium-safe. The main risk with very cheap units is inconsistent wall thickness, which increases fragility. Inspect them carefully upon arrival and test-fit before filling your tank.

Related Reading

• Best Glass Lily Pipe Cleaning Brushes and Tools
• Best Lily Pipe Alternatives for Aquariums on a Budget
• Best Lily Pipe Sets for Aquarium Filtration
• Best Spin Lily Pipes for Aquarium Water Circulation
• Best Glass Lily Pipes for Aquarium Filtration